Exhaust muffler



FIG. 1 is a top view of an exhaust muffler illustrating my new design;

FIG. 2 is a bottom view thereof;

FIG. 3 is a side view thereof;

FIG. 4 is a front view thereof;

FIG. 5 is a rear view thereof; and,

FIG. 6 is a perspective view thereof.

The ornamental design for an exhaust muffler, as shown and described.